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A new method for the synthesis and deposition of tungsten oxide nanopowders directly on the surface of a carbon-fiber-reinforced polymer composite (CFRP) is presented. The CFRP was chosen because this material has very good thermal and mechanical properties and chemical resistance. Also, CFRPs have low melting points and are transparent under ionized radiation. The synthesis is based on the direct interaction between high-power-density microwaves and metallic wires to generate a high-temperature plasma in an oxygen-containing atmosphere, which afterward condenses as metallic oxide nanoparticles on the CFRP. During microwave discharge, the value of the electronic temperature of the plasma, estimated from Boltzmann plots, reached up to 4 eV, and tungsten oxide crystals with a size between 5 nm and 100 nm were obtained. Transmission electron microscopy (TEM) analysis of the tungsten oxide nanoparticles showed they were single crystals without any extended defects. Scanning electron microscopy (SEM) analysis showed that the surface of the CFRP sample does not degrade during microwave plasma deposition. The X-ray attenuation of CFRP samples covered with tungsten oxide nanopowder layers of 2 µm and 21 µm thickness was measured. The X-ray attenuation analysis indicated that the thin film with 2 µm thickness attenuated 10% of the photon flux with 20 to 29 KeV of energy, while the sample with 21 µm thickness attenuated 60% of the photon flux.

The chemical group comprising polycyclic aromatic hydrocarbons (PAHs) has received prolonged evaluation and scrutiny in the past several decades. PAHs are ubiquitous carcinogenic pollutants and pose a significant threat to human health through their environmental prevalence and distribution. Regardless of their origin, natural or anthropogenic, PAHs generally stem from the incomplete combustion of organic materials. Dietary intake, one of the main routes of human exposure to PAHs, is modulated by pre-existing food contamination (air, water, soil) and their formation and accumulation during food processing. To this end, processing techniques and cooking options entailing thermal treatment carry additional weight in determining the PAH levels in the final product. With the background provided, this study aims to provide an improved understanding of PAH occurrence in meat, edible oils, and cereal products. The factors influencing PAH formation, including operational conditions and parameters, product composition, and storage settings, are described. The discussion also addresses reduction directions with respect to influencing factors informing the choice of the employed technique, fuel type, time–temperature settings, and ingredient variations. Considering the disparities caused by wide variations in PAH contamination, challenges associated with PAH control requirements are also outlined in the context of relevant preventive approaches during food processing.

The aim of this work was to develop an analytical method for determining acrylamide in potato-based products by gas chromatography and tandem mass spectrometry analysis (GC-MS/MS) using solid-phase extraction (SPE) clean-up. Different conditions for extraction and clean-up of AA extracts were studied on a potato crisps reference material (RM) with the value of 625 ± 45 μg/kg: the solvent volume used for AA elution, the extraction water temperature, the volume of hexane used, and also the addition of Carrez solutions. The SPE cartridge sorbents contain silica-based C-18 groups (anion and cation exchangers) and polymers (polystyrene-divinylbenzene). After SPE clean-up, extracts were derivatized with bromine compounds. A good efficiency for AA extraction and a cleaned-up extract from this matrix were obtained when the SPE procedure was carried out with water at room temperature, simultaneous with hexane, without Carrez solutions, by using two types of SPE cartridges (Isolute Multimode; Isolute ENV+), and 5 mL of elution solvent. The SPE clean-up procedure functionality was demonstrated by the results obtained in the Food Analysis Performance Assessment Scheme proficiency test (z-score: −0.8) on French fries (precooked) matrix and also by comparative analysis with a laboratory procedure, validated and accredited on cereal-based food matrices, in which liquid–liquid extraction and clean-up through a florisil column were realized (RSD(R) = 2.23–5.10%).

This paper reports the results obtained for a distributed-feedback quantum cascade laser (DFB-QCL) exposed to different fluences of proton particles: 1014, 1015 and 1016 p/cm2. Dedicated laboratory setups were developed to assess the irradiation-induced changes in this device. Multiple parameters defining the QCL performances were investigated prior to and following each irradiation step: (i) voltage-driving current; (ii) emitted optical power-driving current; (iii) central emitting wavelength-driving current; (iv) emitted spectrum-driving current; (v) transversal mode structure-driving current, maintaining the system operating temperature at 20 °C. The QCL system presented, before irradiation, two emission peaks: a central emission peak and a side peak. After proton irradiation, the QCL presented a spectral shift, and the ratio between the two peaks also changed. Even though, after irradiation, the tunning spectral range was reduced, at the end of the tests, the system was still functional.

The aim of this study was to develop and evaluate some validation parameters of a GC-MS sensitive method for the separation, identification, and simultaneous quantification of 18 cis/trans isomers of oleic (FAME C18:1), linoleic (FAME C18:2), and linolenic acid (FAME C18:3) methyl esters. Linearity, sensitivity, and recovery of the developed method were evaluated on calibration solutions. Correlation coefficients (R) were higher than 0.99 in the linear domain for each isomer, the sensitivity of the method was characterized by LOD = 0.03 - 0.05 g/100 g of fat, and LOQ = 0.09 - 0.17 g/100 g of fat, and the recovery ranged between 101.32 - 102.59%. Samples of potato chips were used to demonstrate the applicability of the method and the trans fatty acids (TFA) levels in analyzed sample were below 0.60 g/100 g fat, complying with international recommendations of less than 2 g/100 g of total fat. The proposed GC-MS method allows simultaneous determination of 18 cis/trans isomers (13 trans and 5 cis) of FAME C18 from potato chips.

The aim of this study was to investigate the influence of some pre-treatment applications toward acrylamide mitigation in potatoes fried in domestic conditions modeled after those found in Romania, by using a pan and a fryer. Before being fried in a pan, potato strips were treated in one of the following ways: soaked in cold water for 15, 60, and 120 min (a); soaked in hot water at different combinations of temperatures and durations (60, 70, 80 °C for 5, 10, 15 min) (b); soaked in a NaCl solution (c), and; in a citric acid solution (d) both solutions of 0.05% and 1% concentration for 30 min. For potatoes fried in a fryer, the (a) pre-treatment and soaking in water at 80 °C for 5, 10, and 15 min were applied. Untreated samples were used as a control. French fries were analyzed in terms of moisture and acrylamide content, color, and texture parameters. The pre-treatments applied reduced the acrylamide content in French fries by 4–97% when fried in the pan and by 25–47% when fried in the fryer. Acrylamide content of French fries was negatively correlated with L* parameter and moisture content and positively correlated with a* parameter. The pre-treatments applied can be used successfully by consumers to reduce acrylamide content.

In this paper, we propose a highly selective and efficient gas detection system based on a narrow-band IR metasurface emitter integrated with a resistive heater. In order to develop the sensor for the detection of specific gases, both the microheater and metasurface structures have been optimized in terms of geometry and materials. Devices with different metamaterial structures and geometries for the heater have been tested. Our prototype showed that the modification of the spectral response of metasurface-based structures is easily achieved by adapting the geometrical parameters of the plasmonic micro-/nanostructures in the metasurface. The advantage of this system is the on-chip integration of a thermal source with broad IR radiation with the metasurface structure, obtaining a compact selective radiation source. From the experimental data, narrow emission peaks (FWHM as low as 0.15 μm), corresponding to the CO2, CH4, and CO absorption bands, with a radiant power of a few mW were obtained. It has been shown that, by changing the bias voltage, a shift of a few tens of nm around the central emission wavelength can be obtained, allowing fine optimization for gas detection applications.

A new method for the synthesis and deposition of tungsten oxide nanopowders directly on the surface of a carbon-fiber-reinforced polymer composite (CFRP) is presented. The CFRP was chosen because this material has very good thermal and mechanical properties and chemical resistance. Also, CFRPs have low melting points and are transparent under ionized radiation. The synthesis is based on the direct interaction between high-power-density microwaves and metallic wires to generate a high-temperature plasma in an oxygen-containing atmosphere, which afterward condenses as metallic oxide nanoparticles on the CFRP. During microwave discharge, the value of the electronic temperature of the plasma, estimated from Boltzmann plots, reached up to 4 eV, and tungsten oxide crystals with a size between 5 nm and 100 nm were obtained. Transmission electron microscopy (TEM) analysis of the tungsten oxide nanoparticles showed they were single crystals without any extended defects. Scanning electron microscopy (SEM) analysis showed that the surface of the CFRP sample does not degrade during microwave plasma deposition. The X-ray attenuation of CFRP samples covered with tungsten oxide nanopowder layers of 2 µm and 21 µm thickness was measured. The X-ray attenuation analysis indicated that the thin film with 2 µm thickness attenuated 10% of the photon flux with 20 to 29 KeV of energy, while the sample with 21 µm thickness attenuated 60% of the photon flux. [ABSTRACT FROM AUTHOR]

Nowadays, biscuits are one of the most consumed bakery products and during its processing acrylamide, a chemical contaminant can be formed. The aim of this study was to investigate the influence of the sweetener, fat and the baking conditions on the acrylamide content and color parameters of biscuits. In the formulation recipe of biscuits sweeteners sugar, fructose were used, as well as fat (butter, palm oil). The baking conditions were: 200, and 210 0C for 20, and 30 minutes. The acrylamide content was determined by tandem mass spectrometry (GC-MS/MS). The limit of detection and limit of quantitation of the method were 1.23 μg/kg and 3.7 μg/kg, respectively. Correlations between the acrylamide content and color parameters L*, a*, b* were established. Color parameters were determined with a Konica Minolta colorimeter. The relationship between the acrylamide content and color parameters L*, a*, b* were established by using Pearson correlation. Results showed that regardless of the baking conditions, for the biscuits formulated with sugar and butter, the acrylamide content was significantly smaller (< LOQ - 12.28 μg/kg) than for the ones made with sugar and palm oil (

The chemical group comprising polycyclic aromatic hydrocarbons (PAHs) has received prolonged evaluation and scrutiny in the past several decades. PAHs are ubiquitous carcinogenic pollutants and pose a significant threat to human health through their environmental prevalence and distribution. Regardless of their origin, natural or anthropogenic, PAHs generally stem from the incomplete combustion of organic materials. Dietary intake, one of the main routes of human exposure to PAHs, is modulated by pre-existing food contamination (air, water, soil) and their formation and accumulation during food processing. To this end, processing techniques and cooking options entailing thermal treatment carry additional weight in determining the PAH levels in the final product. With the background provided, this study aims to provide an improved understanding of PAH occurrence in meat, edible oils, and cereal products. The factors influencing PAH formation, including operational conditions and parameters, product composition, and storage settings, are described. The discussion also addresses reduction directions with respect to influencing factors informing the choice of the employed technique, fuel type, time–temperature settings, and ingredient variations. Considering the disparities caused by wide variations in PAH contamination, challenges associated with PAH control requirements are also outlined in the context of relevant preventive approaches during food processing. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess and correlate the acrylamide content, determined by GC-MS/MS, and colour parameters of bread samples prepared using different wheat flours, dough preparation process and baking conditions (230, 240°C/40, 50 min). Our results showed that, regardless of the preparation process and baking conditions, the acrylamide content in bread varied under the effect of flour type. Refined wheat flour bread showed lower acrylamide levels (6.42-12.02 μg/kg) compared to whole-wheat flour bread (9.57-33.04 μg/kg). Acrylamide formation varied in response to dough preparation, ranging between 6.42-15.80 μg/kg for indirect process (IP), and 10.22-33.04 μg/kg for direct process (DP). With respect to the influence of baking conditions, a 10°C increase in baking temperature elevated the acrylamide content by up to 2.87-fold. Similarly, a 10 min extension of baking time resulted in higher acrylamide content (up to 1.30-fold). Moreover, strong negative correlations were observed between the acrylamide content and the L* colour parameter of breads, with r= -0.7522 ÷ -0.8428 for DP, and -0.9796 ÷ -0.9724 for IP. Our findings revealed the lowest acrylamide content achieved in bread prepared using wheat flour, indirect process, and lower baking time and temperature. [ABSTRACT FROM AUTHOR]

The purpose of the study was to evaluate the properties of by-products obtained from the oil industry, to identify the content of bioactive compounds and to test the safety of their reintroduction in the food industry. Three sunflower meals obtained after cold-pressing of whole (WSM), partially dehulled (PSM) and total dehulled (TSM) sunflower seeds were used. A higher protein, ash and fiber content was obtained for WSM, followed by PSM, and TSM meals. Conversely, the lipid content was higher in TSM and PSM, and lower in WSM meals. Sunflower meals are important sources of unsaturated fatty acids (more linoleic than oleic acid), the content ranging between 82.74 and 86.72%. Additionally, sunflower meals represent a significant source of compounds with antioxidant activity. TSM showed the highest concentration of total polyphenols and total flavonoids, while WSM the lowest. The values of antioxidant activity were higher for TSM compared to PSM and WSM. The weak cytotoxic activity at concentrations lower than 6.25 mg/mL, as well as cell viability which is not affected by the action of PSM and TSM but even increases in the case of WSM, give sunflower meals the potential to be added as ingredients in the production of functional foods. [ABSTRACT FROM AUTHOR]

Sunflower (Helianthus annuus L.) crop is grown world wide, under a range of agro-environments. This crop is primarily grown for its edible oil but also for its achenes (confectionery types), both commonly used in human food. With ongoing climate change, sunflower, as a spring crop, could be more exposed to the direct effect of heat stress and to different drought scenarios, resulting in severe yield losses, oil content decrease and alteration of fatty acids composition. The oil concentration in sunflower (whether linoleic or oleic varieties) is valued above the contribution of genotype, of environment but also of the crop management. In our study, with different sunflower hybrids, experimented in different conditions of the environment, we obtained results on oil content and fatty acids composition. The oil content in kernels is influenced by climate. This depends by air temperature in period of anthesis or during grain filing, also by rainfall. The unsaturated fatty acids of sunflower oil are much more affected by genotype and environment than the saturated ones. Cooler regions offer a more favorable climate for the oil and linoleic acid synthesis. There is an indirect relationship for oleic and linoleic content, in sunflower oil. [ABSTRACT FROM AUTHOR]